Wauthier I d'Oisy, seigneur d'Avesnes

How can Ida be the mother of all the children. They were born after her death in 1131. Something is wrong. She must have lived at least up to 1138. Changers were made.

7. WALTER.
He succeeded his father as advocate of Tournai. After the death of his uncle Goswin, he also became lord of Avesnes (SS. XIV, p. 299). He deceased after 1149 J. Vos : S. Nicolas-des-Prés, I1, nO. 13, pp. 28-29).
× Ida, daughter of Everard I, castellan of Tournai; children : Thierry (died young); Nicholas, lord of Avesnes; Everard, bishop of Tournai; four daughters (SS. XIV, pp. 299-300), among whom Petronella (Cartul. Cysoing, no. 32, pp. 41-42); Goswin, advocate of Tournai (Ibidem, loc. cit.); Fastradus (Mir.-Fopp., HI, Pp. 349-350 (1179, July 20)).
(Warlop, 1159)
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Hij is de eerste die zich van Avesnes noemde.

He is the first to call himself van Avesnes.